In recent years, the developments of various electronic devices make our lives become more convenient, and people have more and more diverse requirements on the electronic devices. Accordingly, manufacturers start to use the same electronic devices by adding expansion cards each having a specific function in order to meet the said diverse requirements on the electrical devices. In that case, users can insert expansion cards into an electronic device so as to provide expanded capability to the electronic device.
However, when an electronic device inserted with an expansion card is in operation, the expansion card might generate heat because of the current flowing through.